Method and apparatus for controlling topology

ABSTRACT

A method and an electronic device for controlling a topology are provided. The method includes forming a star topology by directly connecting the electronic device to at least one node, and transmitting and receiving signals with neighboring nodes including the at least one node and determining whether to form the star topology or an extended star topology with the neighboring nodes based on a result of the transmitting and receiving, wherein the star topology is a topology in which the electronic device is directly connected to the neighboring nodes, and wherein the extended star topology is a topology in which the electronic device is directly connected to the neighboring nodes via an already connected node.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims the benefit under 35 U.S.C. §119(a) of a Koreanpatent application filed on Oct. 15, 2013 in the Korean IntellectualProperty Office and assigned Serial number 10-2013-0122861, the entiredisclosure of which is hereby incorporated by reference.

JOINT RESEARCH AGREEMENT

The present disclosure was made by or on behalf of the below listedparties to a joint research agreement. The joint research agreement wasin effect on or before the date the present disclosure was made and thepresent disclosure was made as a result of activities undertaken withinthe scope of the joint research agreement. The parties to the jointresearch agreement are 1) Samsung Electronics Co., Ltd. and 2) KoreaUniversity Research and Business Foundation.

TECHNICAL FIELD

The present disclosure relates to an electronic device, and moreparticularly, to a method and apparatus for controlling a topology byusing Z-wave.

BACKGROUND

As smart home research is being carried out, Machine to Machine (M2M)and Device to Device (D2D) communication technologies are emerging.Further, due to an excessive increase in mobile phone subscribers,mobile network operators are turning their eyes on the M2M technologywhich is communication between two or more objects and does not requirea user's direct intervention. Using the M2M technology, an object candetermine a situation without the user's intervention and can perform anappropriate operation according to the situation. For example, when theM2M technology is applied to a smart phone, the smart phone determineswhether or not the user has arrived at home and controls an airconditioner or a lamp located at the user's house to operate bycommunicating with them.

As Internet Protocol version 6 (IPv6) is developed and can assign aunique IP address to each object, research on the M2M technology isbeing more actively carried out. Since a unique IP address is assignedto each object, each object can access the Internet and can transmitand/or receive data with other objects. As such, an Internet of Thingsis made possible, and various attempts to converge a variety oftechnologies such as M2M and the Internet of Things into a smart homeservice are being made.

Accordingly, there is a demand for research on a protocol such as Z-waveand for a method for communicating between objects more stably by usingZ-wave and using low power.

The above information is presented as background information only toassist with an understanding of the present disclosure. No determinationhas been made, and no assertion is made, as to whether any of the abovemight be applicable as prior art with regard to the present disclosure.

SUMMARY

Aspects of the present disclosure are to address at least theabove-mentioned problems and/or disadvantages and to provide at leastthe advantages described below. Accordingly, an aspect of the presentdisclosure is to provide a method and apparatus for controlling aZ-wave-based network topology in an electronic device.

Another aspect of the present disclosure is to provide a method andapparatus for determining whether to convert a network formed of a startopology into an extended star topology in an electronic device.

Another aspect of the present disclosure is to provide a method andapparatus for connecting nodes existing within a threshold range byusing a star topology in an electronic device.

Another aspect of the present disclosure is to provide a method andapparatus for connecting nodes existing out of a threshold range byusing an extended star topology in an electronic device.

Another aspect of the present disclosure is to provide a method andapparatus for converting a star topology and an extended star topologyin an electronic device.

In accordance with to an aspect of the present disclosure, a method forcontrolling a network topology of an electronic device is provided. Themethod includes forming a star topology by directly connecting theelectronic device to at least one node, transmitting and receivingsignals with neighboring nodes including the at least one node, anddetermining whether to form the star topology or an extended startopology with the neighboring nodes based on a result of thetransmitting and receiving, wherein the star topology is a topology inwhich the electronic device is directly connected to the neighboringnodes, and wherein the extended star topology is a topology in which theelectronic device is directly connected to the neighboring nodes via analready connected node.

In accordance with another aspect of the present disclosure, anelectronic device for controlling a network topology is provided. Thedevice includes a communication module configured to transmit andreceive signals with at least one node, and a topology determinationmodule configured to form a star topology by directly connecting to atleast one node, and to, based on a result of transmitting and receivingsignals with neighboring nodes including the at least one node,determine whether to form the star topology or the extended startopology with the neighboring nodes, wherein the star topology is atopology in which the electronic device is directly connected to theneighboring nodes, and wherein the extended star topology is a topologyin which the electronic device is directly connected to the neighboringnodes via an already connected node.

In accordance with another aspect of the present disclosure, a methodfor forming a network topology of an electronic device is provided. Themethod includes receiving, by the electronic device, a node researchmessage from another electronic device, transmitting a response messageto the other electronic device in response to the node search message,and broadcasting the node search message including address informationof the electronic device.

In accordance with another aspect of the present disclosure, anelectronic device for forming a network topology is provided. Theelectronic device includes a communication module configured tocommunicate with at least one another electronic device, and acontroller configured, if a node search message is received from theother electronic device, to transmit a response message to the otherelectronic device in response to the node search message, and tobroadcast the node search message including address information of theelectronic device.

Other aspects, advantages, and salient features of the disclosure willbecome apparent to those skilled in the art from the following detaileddescription, which, taken in conjunction with the annexed drawings,discloses various embodiments of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of certainembodiments of the present disclosure will be more apparent from thefollowing description taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a view illustrating a block configuration of an electronicdevice for controlling a topology according to an embodiment of thepresent disclosure;

FIG. 2A is a view illustrating a procedure for determining a topologyaccording to a result of transmitting and/or receiving signals in anelectronic device according to an embodiment of the present disclosure;

FIG. 2B is a view illustrating a means for determining a topologyaccording to a result of transmitting and/or receiving signals in anelectronic device according to an embodiment of the present disclosure;

FIG. 3 is a view illustrating a procedure for determining a topology toconnect a node if at least one node is detected in an electronic deviceaccording to an embodiment of the present disclosure;

FIG. 4 is a view illustrating an example of an extended star topologyfor connecting to another node via an already connected node in anelectronic device according to an embodiment of the present disclosure;

FIG. 5 is a view illustrating a procedure for determining a topologyaccording to whether or not there is a change in nodes in an electronicdevice according to an embodiment of the present disclosure;

FIG. 6 is a view illustrating a procedure for assigning a uniqueidentification (ID) to a connected node in an electronic deviceaccording to an embodiment of the present disclosure;

FIG. 7 is a view illustrating a procedure for determining a topologyaccording to a number of hops from a node to an added node in anelectronic device according to an embodiment of the present disclosure;

FIG. 8 is a view illustrating an example of a method for assigning afixed ID in an electronic device according to an embodiment of thepresent disclosure; and

FIG. 9 is a view illustrating a fixed ID system of a topology in anelectronic device according to an embodiment of the present disclosure.

Throughout the drawings, it should be noted that like reference numbersare used to depict the same or similar elements, features, andstructures.

DETAILED DESCRIPTION

The following description with reference to the accompanying drawings isprovided to assist in a comprehensive understanding of variousembodiments of the present disclosure as defined by the claims and theirequivalents. It includes various specific details to assist in thatunderstanding but these are to be regarded as merely exemplary.Accordingly, those of ordinary skill in the art will recognize thatvarious changes and modifications of the various embodiments describedherein can be made without departing from the scope and spirit of thepresent disclosure. In addition, descriptions of well-known functionsand constructions may be omitted for clarity and conciseness.

The terms and words used in the following description and claims are notlimited to the bibliographical meanings, but, are merely used by theinventor to enable a clear and consistent understanding of the presentdisclosure. Accordingly, it should be apparent to those skilled in theart that the following description of various embodiments of the presentdisclosure is provided for illustration purpose only and not for thepurpose of limiting the present disclosure as defined by the appendedclaims and their equivalents.

It is to be understood that the singular forms “a,” “an,” and “the”include plural referents unless the context clearly dictates otherwise.Thus, for example, reference to “a component surface” includes referenceto one or more of such surfaces.

FIGS. 1 through 9, discussed below, and the various embodiments used todescribe the principles of the present disclosure in this patentdocument are by way of illustration only and should not be construed inany way that would limit the scope of the disclosure. Those skilled inthe art will understand that the principles of the present disclosuremay be implemented in any suitably arranged communications system. Theterms used to describe various embodiments are exemplary. It should beunderstood that these are provided to merely aid the understanding ofthe description, and that their use and definitions in no way limit thescope of the present disclosure. Terms first, second, and the like areused to differentiate between objects having the same terminology andare in no way intended to represent a chronological order, unless whereexplicitly stated otherwise. A set is defined as a non-empty setincluding at least one element.

Hereinafter, a method for configuring a Z-wave-based network topology inan electronic device will be explained.

Hereinafter, an electronic device may be a controller for controlling atleast one node (e.g., at least one different electronic device).

FIG. 1 is a view illustrating a block configuration of an electronicdevice for controlling a topology according to an embodiment of thepresent disclosure.

Referring to FIG. 1, an electronic device 100 may include a topologydetermination module 101 and a communication module 103.

The topology determination module 101 may determine a node to be addedto a topology controlled by the electronic device 100 or a node to beremoved from the topology. The topology recited herein refers a thingwhich physically connects network elements (e.g., nodes, etc.) to oneanother, or a connection method of network elements.

The topology determination module 101 may broadcast a message (e.g., adiscovery message) for searching for a node every time a pre-set timearrives or if a pre-set event is detected. Thereafter, the topologydetermination module 101 may determine the node to be added or the nodeto be removed according to whether or not a message is transmittedand/or received.

First, if a message for a topology connection is received, the topologydetermination module 101 may determine whether to add a correspondingnode to the topology based on whether or not the message for searchingfor the node is transmitted.

If the message for searching for the node is broadcasted and the messagefor the topology connection is received from a specific node as aresponse to the corresponding message, the topology determination module101 may connect to the corresponding node. In other words, the topologydetermination module 101 may broadcast the message for searching for thenode, and, if the message for the topology connection is received from aspecific node as a response to the corresponding message, may identify atransmission node of the received message and determine whetherinformation on the identified node exists in a pre-stored database. Forexample, if information on the identified node exists in the database,the topology determination module 101 may perform or maintain aconnection with the corresponding node based on a star topology. Inanother example, if the information on the corresponding node does notexist in the pre-stored database, the topology determination module 101may determine the corresponding node as an additional node, storeinformation on the additional node in the database, and connect to theadditional node based on the star topology.

On the other hand, if the message for the topology connection isreceived from a node to which the message for searching for the node isnot transmitted, the topology determination module 101 may determine thecorresponding node as an additional node, store information on theadditional node in the database, and connect to the additional nodebased on an extended star topology. In this case, the extended startopology refers to a topology which configures a network by connectingto an additional node via an already connected another node withoutdirectly connecting to a node requiring connection.

In addition, if at least one message informing that a new node is addedto the topology is received from a certain node, the topologydetermination module 101 may determine a path and a number of hops tothe electronic device 100 from the new additional node based on themessage which is received first, and may determine a topology to performnode connection. If the number of hops between the additional node andthe electronic device 100 is one, the topology determination module 101may connect to the additional node based on the star topology. On theother hand, if the number of hops between the additional node and theelectronic device 100 is two or more, the topology determination module101 may connect to the additional node based on the extended startopology.

In addition, the topology determination module 101 may assign a uniqueidentification (ID) to the additional node. A method for assigning an IDto an additional node will be explained below with reference todrawings.

The topology determination module 101 may transmit the message forsearching for the node and may determine whether or not to remove acorresponding node from the topology according to whether or not aresponse to the corresponding message is received. If the message forsearching for the node is transmitted to a specific node, but a responseto the corresponding message is not received from the specific node, thetopology determination module 101 may determine the specific node as anode to be removed, may delete information on the specific node from thedatabase, and may disconnect from the corresponding node.

In addition, if a message for removing a node is received from a removalnode or a superordinate node to the removal node, the topologydetermination module 101 may identify the removal node based on thereceived message and may delete information on the corresponding nodefrom the database.

The communication module 103 may transmit and/or receive a communicationsignal with at least one node.

The communication module 103 may broadcast a message for searching for anode every time a pre-set time arrives or if a pre-set event isdetected.

In addition, the communication module 103 may receive a message for thetopology connection from a specific node. For example, the communicationmodule 103 may transmit a message for searching for a node and mayreceive a message for the topology connection from a node which hasreceived the corresponding message as a response to the correspondingmessage. In another example, if the communication module 130 does nottransmit the message for searching for the node, the communicationmodule 130 may receive a message for a topology connection from acertain node. In this case, the received message may include informationon the node which has transmitted the corresponding message.

In addition, the communication module 103 may receive at least onemessage informing that a new node is added to the topology from acertain node, may determine an ID of the added node, and may transmitinformation on the determined ID to the added node. In this case, thereceived message may include information on a path from the added nodeto the electronic device 100 and information on the number of hops.

In addition, the communication module 103 may receive a messageinforming of a removal or an end of a node from a node to be removed ora superordinate node to the node to be removed.

FIG. 2A is a view illustrating a procedure for determining a topologyaccording to a result of transmitting and/or receiving signals in anelectronic device according to an embodiment of the present disclosure.

Referring to FIG. 2A, an electronic device may form a star topology bydirectly connecting to at least one node at operation 201. Specifically,the electronic device may be connected to a center of all network nodesand may form the star topology which directly controls connected nodes.

Thereafter, based on a result of transmitting and/or receiving signalswith neighboring nodes including the at least one node forming the startopology, the electronic device may determine whether to form a startopology in which the electronic device is directly connected to thenode with which the electronic device transmits and/or receives signals,or an extended star topology in which the electronic device is connectedto the node with which the electronic device transmits and/or receivessignals via an already connected node at operation 203.

If a message for searching for a node is transmitted and a message for atopology connection is received from a specific node as a response tothe corresponding message, the electronic device may form the startopology by connecting to the corresponding node.

On the other hand, if a message for the topology connection is receivedfrom a node to which the message for searching for the node is nottransmitted, the electronic device may form the extended star topologyby connecting to the corresponding node.

The electronic device may transmit and/or receive data with nodes byusing Z-wave.

Thereafter, the electronic device may finish the procedure according tothe embodiment of the present disclosure.

FIG. 2B is a view illustrating a means for determining a topologyaccording to a result of transmitting and/or receiving signals in anelectronic device according to an embodiment of the present disclosure.

Referring to FIG. 2B, an electronic device may include a means 211 forforming a star topology by directly connecting to at least one node. Inother words, the electronic device may include a means for connecting toat least one device or node which can be directly controlled by theelectronic device based on the star topology.

In addition, the electronic device may include a means 213 fordetermining whether to form a star topology in which the electronicdevice is directly connected to a node with which the electronic devicetransmits and/or receives signals, or an extended star topology in whichthe electronic device is connected to a node with which the electronicdevice transmits and/or receives signals via an already connected node,based on a result of transmitting and/or receiving signals withneighboring nodes including the at least one node forming the startopology. In this case, the electronic device may include a means forbroadcasting a message for searching for a node and a means forreceiving a message for a topology connection from a node.

In addition, the electronic device may include a means for assigning aunique ID to a connected node.

FIG. 3 is a view illustrating a procedure for determining a topology toconnect a node if at least one node is detected in an electronic deviceaccording to an embodiment of the present disclosure.

Referring to FIG. 3, an electronic device is illustrated, where theelectronic device may establish a network based on a star topology atoperation 301. Specifically, the electronic device may be connected to acenter of all network nodes and may form a star topology which directlycontrols connected nodes.

Thereafter, the electronic device detects a change in nodes at operation303. In other words, the electronic device may detect a node to be addedto the topology or a node to be removed from the topology according to aresult of transmitting and/or receiving data with nodes. In this case,the electronic device may transmit and/or receive data with nodes byusing Z-wave.

Thereafter, the electronic device proceeds to operation 305 to determinewhether or not the detected node exists within a threshold distance.

If the detected node exists within the threshold distance (YES inoperation 305), the electronic device proceeds to operation 307 toconnect the node based on a star topology. In other words, if thedetected node exists within a communication range, the electronic devicemay connect the detected node existing within the communication rangebased on the star topology which directly connects to nodes.

On the other hand, if the detected node does not exist within thethreshold distance (NO in operation 305), the electronic device proceedsto operation 309 to connect the node based on an extended star topology.In other words, if the detected node does not exist within thecommunication range, the electronic device may connect the node whichdoes not exist within the communication range based on the extended startopology which connects to other nodes 403 and 405 via an alreadyconnected node 401, as shown in FIG. 4, which is a view illustrating anexample of an extended star topology for connecting to another node viaan already connected node in an electronic device.

Thereafter, the electronic device may finish the procedure according tothe embodiment of the present disclosure.

FIG. 5 is a view illustrating a procedure for determining a topologyaccording to whether or not there is a change in nodes in an electronicdevice according to an embodiment of the present disclosure.

Referring to FIG. 5, an electronic device may establish a network basedon a star topology at operation 501. Specifically, the electronic devicemay be connected to a center of all network nodes and may form a startopology which directly controls connected nodes.

Thereafter, the electronic device may perform data communication withconnected nodes at operation 503. In this case, the electronic devicemay perform data communication with connected nodes by using Z-wave.

Thereafter, the electronic device proceeds to operation 505 to determinewhether a data transmission succeeds or fails. For example, theelectronic device may determine whether the data transmission succeedsor fails based on whether or not an acknowledgment (ACK) message isreceived in response to the transmitted data.

If the data transmission succeeds, the electronic device resumesoperation 503 to re-perform the operations after operation 503.

On the other hand, if the data transmission fails, the electronic deviceproceeds to operation 507 to re-establish a network. In other words, ifthe data transmission fails, the electronic device may recognize that aproblem related to a node or the data transmission has arisen and mayre-establish a network.

Thereafter, the electronic device proceeds to operation 509 to determinewhether an addition of a node is detected or a removal of a node isdetected. For example, if the electronic device broadcasts a message forsearching for a node, receives a message for a topology connection as aresponse to the corresponding message, and then node informationincluded in the received message does not exist in a pre-storeddatabase, the electronic device may determine that the correspondingnode is added. In another example, if the electronic device broadcasts amessage for searching for a node and a response to the correspondingmessage is not received from a specific node, the electronic device maydetermine that the corresponding node is deleted.

If the addition of a node is detected, the electronic device proceeds tooperation 511 to determine a topology connection method of the addednode. For example, the electronic device may determine whether the addednode exists within a transmission and reception range of the electronicdevice based on data transmitted and/or received with the added node.Then, if the added node exists within the transmission and receptionrange of the electronic device, the electronic device may determine toconnect the node based on a star topology, and, if the added node doesnot exist in the transmission and reception range of the electronicdevice, the electronic device may determine to connect the node based onan extended star topology.

On the other hand, if removal of a node is detected, the electronicdevice proceeds to operation 513 to determine a topology connectionmethod of the other nodes except the removed node. For example, theelectronic device may determine whether or not the other nodes exceptthe removed node, that is, the remaining nodes, exist within thetransmission and reception range of the electronic device 100 based ondata transmitted and/or received with the remaining nodes. Then, if allof the remaining nodes exist within the transmission and reception rangeof the electronic device, the electronic device may determine to connectthe remaining nodes based on a star topology, and, if some of theremaining nodes exist within the transmission and reception range of theelectronic device and some of the remaining nodes do not exist withinthe transmission and reception range of the electronic device, theelectronic device may determine to connect the remaining nodes based onan extended star topology.

Thereafter, the electronic device proceeds to operation 515 to determinewhether the topology connection method determined according to whether anode is added or removed is a star topology or an extended startopology. If the determined topology connection method is the startopology, the electronic device resumes operation 501 to re-perform theoperations after operation 501.

On the other hand, if the determined topology connection method is theextended star topology, the electronic device proceeds to operation 517to establish a network based on the extended star topology. In otherwords, the electronic device may detect a change in nodes, and maydetermine at least one of the star topology and the extended startopology to connect nodes. A method for determining a topologyconnection method according to a change in nodes will be explained belowwith reference to FIGS. 6 and 7.

Thereafter, the electronic device proceeds to operation 519 to performdata communication with connected nodes. In this case, the electronicdevice may perform data communication with connected nodes by usingZ-wave.

Thereafter, the electronic device proceeds to operation 521 to determinewhether a data transmission fails or succeeds.

If the data transmission succeeds, the electronic device resumesoperation 519 to re-perform the operations after operation 519.

On the other hand, if the data transmission fails, the electronic deviceresumes operation 507 to re-perform the operations after operation 507.

FIG. 6 is a view illustrating a procedure for assigning a unique ID to aconnected node in an electronic device according to an embodiment of thepresent disclosure.

Referring to FIG. 6, an electronic device may broadcast a message forsearching for a node at operation 601. For example, the electronicdevice may broadcast a discovery message to neighboring nodes.

Thereafter, the electronic device may receive a message for a topologyconnection as a response to the message for searching for the node atoperation 603. For example, the electronic device may transmit adiscovery message for searching for a node to neighboring nodes, and mayreceive a discovery response message or an ACK message for the topologyconnection as a response to the discovery message from a node which hasreceived the discovery message. Herein, each of the neighboring nodeswhich have received the discovery message may transmit the discoveryresponse message to the electronic device and may include their ownaddress information in the discovery message and may broadcast thediscovery message to neighboring nodes. This is to search other nodesexisting out of a data transmission and reception area of the electronicdevice. In this case, each of the neighboring nodes which has alreadyreceived the discovery message may disregard the discovery messagereceived from other nodes. On the other hand, each of the neighboringnodes which has not received the discovery message may transmit adiscovery response message including the address information included inthe discovery message as a response to the discovery message receivedfrom other nodes.

Thereafter, the electronic device proceeds to operation 605 to determinewhether the received message includes address information of anothernode.

If the received message does not include address information of anothernode (NO in operation 605), the electronic device proceeds to operation613 to assign a unique ID to the node which has transmitted the messagefor the topology connection. For example, if a message for the topologyconnection received from a first node does not include addressinformation of another node, the electronic device may determine thatthe first node exists within the data transmission and reception area ofthe electronic device and is a node with which the electronic device candirectly transmit and/or receive data, may assign a unique ID to thefirst node, and then may transmit the assigned ID to the first node.According to an embodiment of the present disclosure, the electronicdevice may assign IDs of a first tier to nodes with which the electronicdevice can directly transmit and/or receive data. For example, as shownin FIG. 8, which illustrates an example of a method for assigning afixed ID in an electronic device according to an embodiment of thepresent disclosure, nodes which directly communicate with the electronicdevice serving as a controller may be assigned IDs of the first tierexpressed as single numbers like 1, 2, and 3 (e.g., see referenceelements 801, 802, 803, as illustrated in FIG. 8).

Thereafter, the electronic device may receive an ACK in response to theunique ID at operation 615. If a unique ID is assigned to a specificnode, but an ACK is not received in response to the unique ID, theelectronic device may re-transmit the unique ID to the specific node apredetermined number of times to receive the ACK.

Thereafter, the electronic device proceeds to operation 617 to connectthe node from which the ACK is received to a star topology.Specifically, the electronic device may directly connect to thecorresponding node based on the star topology.

Thereafter, the electronic device resumes operation 601 to re-performthe operations after operation 601.

As a result of determining at operation 605, if the received messageincludes address information of another node (YES at operation 605), theelectronic device may determine that the received message is a messagethat is received from still another node which has received thediscovery message from another node corresponding to the addressinformation, and may assign still another node a unique ID indicatingthat still another node which is a transmission node of the receivedmessage is a subordinate node to another node corresponding the addressinformation at operation 607. For example, if a message received from asecond node includes address information of a first node, the electronicdevice may determine that the second node exists out of the datatransmission and reception area of the electronic device and thus cannotdirectly transmit and/or receive data with the electronic device and cantransmit and/or receive data with the electronic device via the firstnode existing within the data transmission and reception area of theelectronic device, may determine the second node as a subordinate nodeto the first node, that is, a second tier node, and then may assign alower tier ID related to the ID assigned to the first node to the secondnode. The electronic device may transmit the lower tier ID assigned tothe second node to the second node via the first node. For example, ifthe ID assigned to the first node is “1”, the lower tier IDs related to“1” may have a form derived from “1”, like “1-1, 1-2, 1-3, . . . 1-9”.If the ID assigned to the first node is “1-1”, the lower tier IDsrelated to “1-1” may have a form derived from “1-1” like “1-1-1, 1-1-2,1-1-3, . . . , 1-1-9”. For example, as shown in FIG. 8, if the IDassigned to the first node is “ID: 1 (801)”, the electronic device mayassign the second node communicating with the electronic device via thefirst node “ID: 1-1 (811)”. In another example, if the ID assigned tothe first node is “ID: 1 (801)” and the ID assigned to the second nodeis “ID: 1-1 (811)”, the electronic device may assign a third node and afourth node communicating with the electronic device via the first nodeand the second node “ID: 1-1-1 (821)” and “ID: 1-1-2 (823)”,respectively. If the IDs are assigned in this way, the ID structure maybe as shown in FIG. 9, which illustrates a fixed ID system of a topologyin an electronic device according to an embodiment of the presentdisclosure. For example, the ID structure configured with reference tofour (4) hops may include four (4) fields (or memory cells) in which“ID1-ID2-ID3-ID4” are recorded in sequence, as shown in FIG. 9. Forexample, if the ID assigned to the first node is “1”, the ID “1” of thefirst node may be recorded on the “ID 1” field, which is the first fieldof the four fields, and if the ID assigned to the fourth node is“1-1-2”, the first “1” of the ID of the first node may be recorded onthe ID1 field, the second “1” may be recorded on the ID2 field, and thethird “2” may be recorded in the ID3 field. In this way, the IDstructure may be a fixed structure. According to another embodiment, inan ID structure configured with reference to four (4) hops, each of“ID1-ID2-ID3-ID4” may be formed of n bits. For example, if the IDassigned to the first node is “1”, an ID structure of the first node maybe “0000 0000 0000 0001”, and if the ID assigned to the fourth node is“1-1-2”, an ID structure of the second node may be “0000 0010 00010001”.

Thereafter, the electronic device may receive an ACK in response to theassigning of the ID from the lower tier node at operation 609. If theunique ID is assigned to the lower tier node, but the ACK is notreceived in response to the unique ID, the electronic device mayre-transmit the unique ID to the lower tier node a predetermined numberof times to receive the ACK.

Thereafter, the electronic device proceeds to operation 611 to connectthe lower level node to which the unique ID is assigned based on anextended star topology. Specifically, the electronic device may connectto the lower level node via an already connected node based on theextended star topology.

Thereafter, the electronic device resumes operation 601 to re-performthe operations after operation 601.

In the above example, a method for assigning an ID of a fixed structurehas been described. However, according to an embodiment of the presentdisclosure, a dynamic ID may be assigned. For example, a pre-setidentifier value may be used to indicate which node is connected with anode having a corresponding ID, that is, which node allows the node tocommunicate with the electronic device serving as a controller. If Hexdata is used and the identifier value is set to AF, an identifier mayexist in the 10^(th) bit and the 15^(th) bit, and, if the identifiervalue is set to 14 C, an identifier may exist in the 1^(st) bit, 4^(th)bit, and 12^(th) bit. The hierarchy may be classified by such anidentifier value. If the ID is assigned by the identifier as describedabove, the hierarchy can be classified freely in comparison with thefixed ID structure. Therefore, even if many nodes exist in a specificlevel, the ID can be actively assigned.

As described above, by assigning nodes which do not directly communicatewith the electronic device and communicate via a specific node an IDindicating that the nodes are subordinate to the specific node, a pathto reach a destination node can be indicated based on the ID, and thusrouting can be performed without requiring a separate routing table.

FIG. 7 is a view illustrating a procedure for determining a topologyaccording to a number of hops from a node to an added node in anelectronic device according to an embodiment of the present disclosure.

Referring to FIG. 7, an electronic device may receive a node changemessage at operation 701. The electronic device may receive a messageinforming that a new node is added or a message informing that aspecific node is removed from a node constituting an already formednetwork topology. In addition, the electronic device may directlyreceive a message informing of an addition of a node from a new nodewhich does not constitute the already formed network topology, and maydirectly receive a message informing of an end of a specific node fromthe specific node constituting the already formed network topology. Forexample, if a specific node is added to a network, the specific node maytransmit a start message informing of its existence to neighboringnodes, and the neighboring nodes may include their own addressinformation in the start message and may forward the start message tothe electronic device serving as a controller of the already formednetwork topology. In another example, if a specific node is removed froman already formed network, the specific node may transmit an end messageinforming of its end to neighboring nodes, and the neighboring nodes mayinclude their own address information in the end message and may forwardthe end message to the electronic device serving as a controller of thealready formed network topology.

Thereafter, the electronic device proceeds to operation 703 to determinewhether the received message is a node addition message or a noderemoval message.

If the received message is the node addition message, the electronicdevice proceeds to operation 705 to determine a number of hops from theadded node to the electronic device. For example, the added node may setthe number of hops to 1 in the start message for informing its existenceand may transmit the start message to neighboring nodes. If theneighboring nodes forward the received start message, the neighboringnodes may increase the number of hops of the corresponding message by 1.Accordingly, the electronic device may determine the number of hops fromthe added node to the electronic device 100 based on the number of hopsincluded in the received message.

Thereafter, the electronic device determines whether or not thedetermined number of hops is greater than 1 at operation 707. If thedetermined number of hops is greater than 1 (YES in operation 707), theelectronic device proceeds to operation 709 to form a network based onthe added node and the extended star topology.

Thereafter, the electronic device may finish the procedure according tothe embodiment of the present disclosure.

On the other hand, as a result of determining at operation 707, if thedetermined number of hops is 1 (NO in operation 707), the electronicdevice proceeds to operation 711 to form a network based on the addednode and the star topology.

Thereafter, the electronic device may finish the procedure according tothe embodiment of the present disclosure.

As a result of determining at operation 703, if the received message isthe node removal message, the electronic device proceeds to operation713 to remove a path of the removed node.

Thereafter, the electronic device may finish the procedure according tothe embodiment of the present disclosure.

The various embodiments and all function operations described in thepresent disclosure may be implemented by computer software, firmware, orhardware, or a combination of one or more of them, including theconfiguration disclosed in the present disclosure and equivalentconfigurations. In addition, the various embodiments described in thepresent disclosure may be implemented by one or more modules of computerprogram instructions executed by one or more computer program products,that is, a data processing device, or encoded on a computer-readablemedium for controlling the operation of this device.

The computer-readable medium may be a machine-readable storage medium, amachine-readable storage substrate, a memory device, a configuration ofa material influencing a machine-readable radio-wave stream, or acombination of one or more of them. The term “data processing device”includes a programmable processor, a computer, or any apparatus, device,and machine for processing data, including a multi-processor orcomputer. The apparatus may include a code which is added to hardwareand generates an execution environment for a corresponding computerprogram, for example, a code constituting processor firmware, a protocolstack, a database management system, an operating system, or acombination of one or more of them.

While the present disclosure has been shown and described with referenceto various embodiments thereof, it will be understood by those skilledin the art that various changes in form and details may be made thereinwithout departing from the spirit and scope of the present disclosure asdefined by the appended claims and their equivalents.

What is claimed is:
 1. A method for controlling a network topology of anelectronic device, the method comprising: forming a star topology bydirectly connecting the electronic device to at least one node;transmitting and receiving signals with neighboring nodes comprising theat least one node; and determining whether to form the star topology oran extended star topology with the neighboring nodes based on a resultof the transmitting and receiving, wherein the star topology is atopology in which the electronic device is directly connected to theneighboring nodes, and wherein the extended star topology is a topologyin which the electronic device is directly connected to the neighboringnodes via an already connected node.
 2. The method of claim 1, whereinthe determining of whether to form the star topology or the extendedstar topology comprises: broadcasting a message for searching for anode; receiving a response message from a first node among theneighboring nodes in response to the message for searching for the node;and determining whether to form the star topology or the extended startopology with the first node based on whether the response messagecomprises address information of another node, such that the startopology is formed with the first node if the response message does notcomprise an address of the other node, and such that the extended startopology is formed with the first node through the other node if theresponse message comprises the address of the other node.
 3. The methodof claim 1, further comprising assigning a node connected based on thestar topology or the extended star topology a hierarchicalidentification (ID) indicating a connection structure of the electronicdevice.
 4. The method of claim 3, wherein the assigning of thehierarchical ID comprises assigning a node directly connected with theelectronic device a first tier ID, and assigning a node connected withthe electronic device via at least one different node a lower tier IDrelated to an ID of the at least one different node.
 5. The method ofclaim 3, wherein the hierarchical ID indicates a tier of a node assigneda corresponding ID and a node related to the node assigned thecorresponding ID by using a plurality of memory fields.
 6. The method ofclaim 3, wherein the hierarchical ID indicates a tier of a node assigneda corresponding ID and a node related to the node assigned thecorresponding ID by using a bit string divided into a plurality of bitstrings.
 7. The method of claim 3, wherein the hierarchical ID indicatesa tier of a node assigned a corresponding ID and a node related to thenode assigned the corresponding ID by using a pre-set identifier value.8. The method of claim 3, wherein a data transmit and receive path isset based on the hierarchical ID assigned to a node without a routingtable.
 9. The method of claim 1, further comprising: detecting that adata transmission and reception of the electronic device with at leastone of nodes forming the star topology or the extended star topologyfails more than a predetermined number of times; and re-determiningwhether to form the star topology with the node with which theelectronic device transmits and receives the signals, or the extendedtopology with the node with which the electronic device transmits andreceives the signals.
 10. The method of claim 1, further comprising:receiving a start message indicating a new node; determining whether toform the star topology or the extended star topology with the new nodebased on address information included in the start message; andassigning a hierarchical identification (ID) to the new node based onthe address information.
 11. The method of claim 1, further comprising:receiving an end message regarding an already connected node; andremoving a node which transmits the end message from an already formedstar topology or extended star topology.
 12. A method for forming anetwork topology of an electronic device, the method comprising:receiving, by the electronic device, a node search message from anotherelectronic device; transmitting a response message to the otherelectronic device in response to the node search message; andbroadcasting the node search message including address information ofthe electronic device.
 13. The method of claim 12, further comprising:receiving a response message comprising the address information of theelectronic device from at least one neighboring node as a response tothe node search message including the address information of theelectronic device; and forwarding the received response message to theother electronic device.
 14. An electronic device for controlling anetwork topology, the electronic device comprising: a communicationmodule configured to transmit and receive signals with at least onenode; and a topology determination module configured to form a startopology by directly connecting to at least one node, and to, based on aresult of transmitting and receiving signals with neighboring nodescomprising the at least one node, determine whether to form the startopology or the extended star topology with the neighboring nodes,wherein the star topology is a topology in which the electronic deviceis directly connected to the neighboring nodes, and wherein the extendedstar topology is a topology in which the electronic device is directlyconnected to the neighboring nodes via an already connected node. 15.The electronic device of claim 14, wherein the communication module isfurther configured to broadcast a message for searching for a node, andto receive a response message from a first node among the neighboringnodes in response to the message for searching for the node, and whereinthe topology determination module is further configured to determine,based on whether or not the response message comprises addressinformation of another node, whether to form the star topology or theextended star topology, such that, if the response message does notcomprise an address of the other node, the topology determination moduleforms the star topology with the first node, and such that, if theresponse message comprises the address of the other node, the topologydetermination module forms the extended star topology with the firstnode through the other node.
 16. The electronic device of claim 14,wherein the topology determination module is further configured toassign a node connected based on the star topology or the extended startopology a hierarchical identification (ID) indicating a connectionstructure of the electronic device.
 17. The electronic device of claim16, wherein the topology determination module is further configured toassign a node directly connected with the electronic device a first tierID, and to assign a node connected with the electronic device via atleast one different node a lower tier ID related to an ID of the atleast one different node.
 18. The electronic device of claim 14, whereinthe communication module is further configured to receive a startmessage indicating a new node, and wherein the topology determinationmodule is further configured to determine whether to form the startopology or the extended star topology with the new node based onaddress information included in the start message, and to assign ahierarchical identification (ID) to the new node based on the addressinformation.
 19. An electronic device for forming a network topology,the electronic device comprising: a communication module configured tocommunicate with at least one another electronic device; and acontroller configured, if a node search message is received from theother electronic device, to transmit a response message to the otherelectronic device in response to the node search message and tobroadcast the node search message including address information of theelectronic device.
 20. The electronic device of claim 19, wherein thecontroller is further configured to receive a response messagecomprising the address information of the electronic device as aresponse to the node search message including the address information ofthe electronic device from at least one neighboring node, and to forwardthe received response message to the other electronic device.